The Internet is currently connected to a large number of server networks around the world and also an enormous and effective information providing medium. The Internet is utilized for emails, newsgroups, file transmissions, information transfers, searches, etc. Also, many people express their interests in various fields of arts, literatures, sciences, medical sciences, entertainments, sports, politics, science technologies, industries, economics, etc., via their own homepage. Currently, the Internet provides a huge amount of daily news articles in association with each of these fields. Accordingly, an Internet service user utilizes an Internet search service to select and obtain only necessary information from various kinds of information.
In a conventional search method, as a user inputs a keyword, and a search result based on the keyword is provided. The user may obtain information by selecting particular information from the provided search result. However, when another user inputs the keyword, the another user may want to select different information from the provided search result. Accordingly, a personalized search method of providing a different search result for each user based on user information has started being utilized. As an example, when a user who subscribes to a search service logs into the search service and requests a search, a search system may provide the user with a specialized search result by utilizing user information with respect to the user's address, sex, occupation, etc.
However, according to the conventional art, a personalized search service may be provided only when each user's information is maintained. When the user does not log into a search service, the personalized search service may not be provided.